The present inventions relate to batteries and battery systems. More specifically, the present inventions relate to lithium batteries (e.g., lithium-ion batteries, lithium-polymer batteries, etc.) and systems using such batteries that include systems for managing one or more batteries, battery modules, or battery cells when predetermined conditions have been met.
It is known to provide batteries for use in vehicles such as automobiles. For example, lead-acid batteries have been used in starting, lighting, and ignition applications. More recently, hybrid vehicles have been produced which utilize a battery (e.g., a nickel-metal-hydride battery) in combination with other systems (e.g., an internal combustion engine) to provide power for the vehicle.
It is generally known that lithium batteries perform differently than nickel-metal-hydride batteries. In some applications, it may be desirable to obtain the enhanced power/performance of a lithium battery. However, the application of lithium battery technology may present design and engineering challenges beyond those typically presented in the application of conventional nickel-metal-hydride battery technology.
The design and management of a lithium battery system that can be advantageously utilized in a hybrid vehicle may involve considerations such as electrical performance monitoring, thermal management, and containment of effluent (e.g., gases that may be vented from a battery cell). For example, it may be desirable to monitor the temperature of individual battery cells within a lithium battery system to ensure that thermal runaway conditions are not met. When predetermined conditions are met, it may be desirable to provide a system for managing one or more batteries, battery modules, or battery cells. It may be further desirable for this battery management system to balance the cells or modules until conditions change. It may also be desirable to provide a system for disconnecting a battery, battery module, or cell from the system when a battery cell approaches a predetermined temperature threshold.